Well tools for perforating pipe



July 10, 1956 Filed April e, 1953 J. V. FREDD WELL TOOLS FOR PERFORATING PIPE ik sa@ 5 Sheets-Sheet l ATTORNEY July 1o, 1956 J. v FREDD 2,753,935

WELL. TOOLS FOR PERFORATING PIPE John l. Fr edd JNVENToR.

BY l 2 a ATTORNEY J. V. FREDD July 10, 1956 WELL TOOLS FOR PERFORATING PIPE 5 Sheets-Sheet 3 Filed April 6, 1953 MN Fm n .n M L V. B H m.. M F m.. F 0 l m.. F

A 7' TORNE Y United States Patent O WELL TOOLS FOR PERFORATING PIPE John V. Fredd, Dallas, Tex. Application April 6, 1953, Serial No. 346,975 9 Claims. (Cl. 164-.3)

This invention relates to well tools and more partcularly to a well tool for perforating tubing.

The tubing of tubing strings of wells frequently must be perforated at predetermined positions in the well. Well tools for perforating the tubing should preferably be capable of being lowered into the tubing string as a single compact unit by means of a flexible line for ease and rapidity of handling, and to permit their operation under pressure. The tools should be of relatively short length because of the extreme difficulty of lowering tools of excessive length in tubing which may be crooked due either to the drift of the well in drilling or to other reasons, Moreover, such well tools should preferably be operable to perforate the tubing by upward jars delivered thereto by means of the flexible line. Well tools requiring downward jarring imparted through the flexible line are not easily operable or adapted for use in wells filled with heavy and viscous well fluids which tend to absorb the force of downward jars lso that a relatively small force is delivered to operate the perforating mechanism; and, as a result, the number of downward jars or strokes required to cause the perforating tool to penetrate the tubing may be so great as to require many hours of downward jarring and also cause fatigue and resultant breakage of the flexible line. In wells of great depth, the extreme length of the flexible line causes an excessive loss of force in the line so that the force of the downward jars delivered to the perforating tool is extremely attenuated. In such wells also many hours of downward jarring may be necessary to effect the perforation of the tubing.

Accordingly, an object of the invention is to provide a new and improved tubing perforating well tool.

Another object of the invention is to provide a new and improved tubing perforating well tool which is lowerable into and removable from a tubing string as a single unit by means of a flexible line whereby only a single lowering operation is required to position the perforating tool in and form a perforation at a predetermined position in a tubing string.

Still another object of the invention is to provide a well tool, of the type described, which is of short length for ease of passage through the tubing strings which may be crooked due to the drift of the well or for other reasons.

A further object of the invention is to provide a well tool, of the character described, whose perforating mechanism is operable by upward force applied thereto through the flexible line by which the tool is lowered and removed from the tubing string.

Another important object of the invention is to provide a well tool, of the character described, which may be withdrawn from the tubing string at any stage of its operation so that the tubing need not be perforated simply because the cycle of operation of the well tool has been commenced.

Further objects and advantages of the invention will readily be apparent from the reading of the following lCe description of a device constructed in accordance with the invention, and reference to the accompanying drawings thereof, wherein:

Figures 1 and 2 are vertical, partly sectional7 views of a tubing perforating tool showing it as it appears while it is being lowered through a tubing string.

Figure 3 is a horizontal cross sectional view taken on the line 3 3 of Figure 1,

Figure 4 is a fragmentary side elevation of the tool shown in Figures l and 2 and showing the tool turned degrees about its longitudinal axis,

Figures 5 and 6 are vertical partly sectional views of the perforating tool in a tubing string showing the manner in which its downward movement is stopped at a desired position in the tubing string by a coupling stop, and showing the perforating punch of the tool moved into engagement with the wall of the tubing,

Figure 7 is a horizontal cross-sectional View taken on the line 7-7 of Figure 5,

Figures 8 and 9 are vertical partly sectional views, similar to Figures 5 and 6, showing the manner in which the perforating punch penetrates the tubing wall in an intermediate stage of the operation of the perforating tool.

Figures 10 and 11 are vertical sectional views, similar to Figures 8 and 9, showing the punch after the perforating operation has been completed,

Figures 12 and 13 are vertical sectional views showing the manner in which the perforating punch may be retracted before initiation or before completion of the perforating operation, and

Figure 14 is a side View of stop for the perforator.

In the drawings, the numeral 10 designates a perforating tool constructed in accordance with the invention, which includes an elongate tubular body or carrier 11 internally threaded at its upper end to receive and hold the lower externally threaded end of a connecting member` or sub 12. The upper end of the sub 12 is threaded whereby it may be attached to a flexible line lowering and jarring mechanism having a suitable coupling or socket (not shown) well known in the art.

The carrier has an elongate longitudinally extending slot or window intermediate its ends in which a perforating punch 14 is pivotally mounted at one end on a pin 15. The ends of the pin are square or flattened on three sides and are received in correspondingly shaped aligned recesses in the carrier. The ends of the pin 15 have been attened on three sides in order to provide the pin with a larger bearing surface to withstand the heavy forces imposed upon it by the perforating punch 14 during actual penetration or perforation of the tubing wall by the punch.

The carrier is provided with which the rounded end 17 of the punch travels, and which provides a bearing surface 18 for the rounded end so that some of the force exerted by the punch is borne by this surface to help reduce the strain on the punch pin 15. The carrier is also formed with an external protuberance or boss 19 disposed adjacent the recess 16 and opposite the window 13 which may bear against the internal wall surface of tubing while the punch is being pivoted to perforate the tubing.

a modied form of the an internal recess 16, in

The punch has a pin 20 mounted therein, the ends of said pin extending outwardly from both sides of the punch and received in lateral guides slots 21 of a control frame 22 disposed in the carrier for sliding movement between the longitudinal edges 23 and 24 of the window 13. The control frame is also provided with a central longitudinal slot 25 through which the punch extends. The lateral guide slots Z1, of course, open on the longitudinal slot 25.

Attached to the control frame 22, by means of screws 26, are an upper slide 27 and a lower slide 28 which are received in the longitudinal bore 11a of the carrier extending in opposite directions from points adjacent the ends of the internal recess 18 and on opposite sides of the internal flanges or abutments 29 formed in said longitudinal bore of the carrier. The abutments are provided with a pair of aligned recesses 3Q which receive the flattened ends of the punch pin 15. It will be seen that the engagement of the carrier frame 22 with the edges 23 and 24 detining the window 13 of the carrier prevents lateral displacement of the punch 14 relative to the car- Iier. It will also be seen that upon downward movement of the control frame 22 relative to the carrier the engagement of the pin 20 in the lateral guide slots 21 of the control frame causes the punch 14 to pivot downwardly about the punch pin 15, thus causing the punchs cutting end 31 to swing outwardly o f the carrier to engage thetubing wall.

The upper Slide 27 is provided with an annulus 32 concentric with the longitudinal axis of the carrier, which receives the lower end of a biasing spring 33 whose upper end is disposed in the longitudinal bore 34 of the sub 12. The spring 33 biases the control frame downwardly with respect tothe carrier.

The lower end of the carrier is internally threaded to receive a retaining plug 3,5 whose upper end provides an` upwardly facing stop shoulder 36 which extends inwardly into'the central passage of the carrier. A connector sleeve 37 extends slidably upwardly through the retaining plug into the carrier and has an enlarged upper end 38which provides a downwardly facing stop shoulder 39, which is adapted to engage the stop shoulder 36 of the retaining plug to limit downward movement of the connector sleeve with respect to the carrier.

A plunger 40 has its lower end disposed in the centralV bore 41 of the connector sleeve and is secured to said sleeve` by a shear pin 42. The upper end of the plunger is formed with a disk 43 having an upwardly extending diametric ange or rib 44, which extends into a correspondingly shaped slot 45 in the lower end of the slide and. the, adjacent side of the control frame. The rib 44 prevents rotary movement of the plunger and the connector sleeve relative to the carrier.

It will now be seen that the plunger 40 supports and holds the control frame 22 in the raised position shown in Figures l and 2 against the force exerted by the spring 33 and thus prevents the punch 14 from moving to extended perforating position, and that theV control frame may be moved downwardly with respect to theL carrier only whenl the shear pin 42 is sheared.

The lower end of the connector sleeve 37 is provided with a locator body 46 which is tubular in form, the, lower end of the connector sleeve 37 being disposed in the upper end of the central bore 47 of the locator body and being rigidly secured thereto by a pin 47a or in any other suitable manner. A stop member 48, shown to be designed to engage in a coupling recess, is pivotally mount,- ed within the central bore 47 by means of a pin 49 for movement between the positions shown in FiguresV 2 and 6. It will be seen that in the position shown in Figure 2, the straight side portion S of the stop member is disposed in a longitudinal slot 51 of the locator body 46, and that the stop member is pivotable about the pin 49- to the position shown in Figure 6 wherein the opposite curved edge portion S2 of the stop member extends laterally outwardly of the locator body 46 through the slot 53 thereof.

The stop member is yieldingly held in either of the two positions by an over-center or toggle mechanism which includes a link 54 pivotally secured to the stop member by a pin 55 which is laterally displaced to one side of the central axis of the pivot pin 49 of the s top member` when the stop member is in the position shown in Figure 2 and which islaterally displaced to the Other side of the central axis of the pivot pin 49 when the stop member is in the position shown in Figure 6. The opposite upper end of the link 54 is pivotally secured to a plunger 56 by means of a pin 57 so that the upper end of the link and the stop member pivot about parallel horizontal axes which are vertically aligned on the central longitudinal axis of the tool. The plunger 56 has a bifurcated dependent portion 5S forming a slot in which the upper end of the link is disposed, the lower end of the link being disposed in a slot 59 of the stop member.

The plunger S6 is biased downwardly by a spring 60 which is disposed in the central bore 47 of the locator body, the lower end of the spring bearing against the upper end of the plunger 56 and the upper end against an annular internal shoulder 61 of the locator body.

A dog 62 has an inner end disposed in the slot 59 of the stop member and pivotally secured thereto by a pin 63. The outer end of the dog projects outwardly and upwardly from the slot 59 when the stop member is in the position shown in Figure 2. The dog is yieldingly held in this position by a spring 64 whose outer end is secured to the dog in a drilled hole or in any other conventional manner and whose inner end is received in a bore in the coupling stop and rigidly held therein by a set screw 65. The dog is provided with a tubing engaging insert or shoe 66 of hard metal or the like at its outer end. The tip ot the dog may be provided with teeth or serrations, if desired, to permit its use at any point in the pipe.

In use, the perforating tool is lowered into a tubing string 67 composed of sections joined by collars or couplings 69. Such lowering is perferably done by means of a flexible line (not shown) attachedy to the threaded upper end of the sub 12 by a suitable fitting or coupling. The various elements of the perforating tool are inY the positions shown in Figures l and 2, with the punch 14y being in retracted position and the dog 62 extending outwardly and having its shoe 66 yieldably held: against the inner wall of the tubing sections due to the action of the spring 64. The stop member is held in the position shown in Figure 2 by the force exerted by the spring 60, with the upper side edge 70 of the stop member contacting the locator body and thus limiting clockwise rotation of the coupling stop.

When the perforating tool has been lowered to the desired' depth, it is lifted in the tubing string, the outer end of the dogl 62 moving outwardly into the recess 71 formed by acoupling 69 and the adjacent upper and lower ends- 72 and 73- of two adjacent sections of the irst such recess of the tubing string it reaches in this upward movement. The shoe 66 then contacts` the lower end 73 of a tubing sectionand is pivoted counterclockwise about the pin 63 as the upward movement of the tool is continued, thus causing the coupling stop to pivotcounterclockwise against the resistance of the spring 60. As thepin 55 which connects the link 54 passes the vertical-v longitudinal axis on which lie the central axes of the pins 49- and 57, the spring 60 moves the plunger 56 downwardly to rotate the stop counterclockwise about the pivot pin 49. The dog 62 is thus retracted to the position shown in Figure 6 and the curved edge portion 52 of the stop member extends outwardly through the slot 53 to` contact the internal wall of the upper tubing section.

The perforating tool is then lowered again until the curved edge portion of the coupling stop enters into the rccesstl'l of? the tubing string as the coupling stop rotates counter-clockwise and its stop shoulder 75 contacts the upper end 72 of the lower section, thus preventing further downward movement of the perforating tool in the tubing string.

Downward jars are then imparted to-the sub i2 in the usual.V manner until thev pin 42 is sheared` to free the plunger 40.for downward movement through the central bore 41 of the connector sleeve 37. This permits the spr-ingl 33k to.` move the control' frame 22 downwardly through the carrier 11, causing the punch 14 to be pivoted clockwise about its pivot pin 15, due to the engagement of the pins 20 in the slots of the control frame, until the leading end or point 76 of the punch contacts the internal wall of the upper tubing section. The spring 33 then firmly holds this leading end of the punch in engagement with the tubing section. Downward movement of the carrier relative to the connector sleeve is limited by the collar 77 on the connector sleeve.

Upward jars are then imparted to the sub 12, causing the carrier to move upwardly in the tubing. During this upward movement, the punch 14 continues to pivot in a clockwise direction and progressively penetrates the wall of the tubing section as is shown in Figures and 8 of the drawings. Continued upward movement of the carrier causes the punch to swing approximately 180 degrees to the downward retracted position shown in Figure l() wherein the punch is out of engagement with the tubing and is disposed wholly within the carrier. The perforating operation is now completed and the tool may be lifted upwardly and out of the tubing string, the coupling stop being free to pivot clockwise against the resistance of the spring 60 upon encountering obstructions in its upward movement through the tubing string, the curved edge portion 52 camming the coupling stop inwardly as it meets such obstructions.

It is sometimes found desirable or necessary to withdraw the perforating tool before the perforation of the tubing has been commenced or, if it has been commenced, before the perforation is completed. To permit such early withdrawal of the tool from the tubing string, the collar 77 is secured on the connector sleeve by a shear pin 78 and a pair of tumblers 79 disposed in a pair of lateral apertures 80 in the connector sleeve are biased outwardly by a spring 81. The tumblers are normally held in retracted position since their outer ends engage the inner wall of the retaining plug 3S.

If it now becomes necessary or desirable to withdraw the perforating tool after the shear pin 42 has been sheared, further downward jars are imparted to the sub, and since the retaining plug now rests on the collar 77, as is shown in Figure 6, the shear pin 78 is sheared and the carrier 11 may slide down on the connector sleeve, the collar also sliding down. When the carrier moves downwardly on the connector sleeve the tumblers 79 are moved past and above the upper end of the retaining plug and move outwardly to contact the internal wall of the carrier. The engagement of the tumblers 79 with the upper end or stop shoulder 36 of the retaining plug then limits downward movement of the connector sleeve in the carrier and holds it in a raised position. In this position the upper end of the connector sleeve abuts the lower surface of the disk 43 of the plunger 40 and holds the control frame 22 against downward movement, and thus holds the punch 14 in the retracted position, as shown in Figures l2 and 13. The tool can then be withdrawn upwardly from the tubing before the perforalting operation has begun. The same procedure is followed to retract the punch after the perforating operation has commenced and before it has been fully completed.

lt will be seen now that a new and improved perforating tool has been provided which includes a carrier 11, a punch 14 retractably mounted in the carrier and having a cutting edge 31 movable outwardly through a window in the carrier to contact and perforate tubing, a spring 33 biasing the punch toward outwardly projecting position, and a shear pin 42 and plunger 40 holding the punch in retracted position so that the punch is released to contact the tubing when the pin 42 is sheared by downward jars delivered to the carrier, whereupon the punch may be pivoted through approximately 180 degrees to penetrate the tubing upon upward jars then being imparted to the carrier. It will also be seen that a connector sleeve 37 is mounted in the central bore of the carrier and extends downwardly therefrom, the lower end of the connector sleeve being provided with a locator body having an expansible stop member 48 which is movable outwardly by a toggle mechanism to limit downward movement of the perforating tool, the stop member having a dog 62 which swings it outwardly upon upward movement of the tool through a tubing string.

It will also be seen that the force necessary to cause the punch 14 to perforate the tubing is imparted to the tool by upward jarring so that the tool may be easily and quickly operated even in wells having thick and viscous fluids, or in wells of great depth, the force needed to shear the pin 42 being relatively small so that the pin may be easily sheared by downward jars of relatively small force applied to the carrier. Moreover, it will be seen that the connector sleeve is provided with tumblers 79 which cooperate with a stop shoulder 36 of the carrier to hold the punch in retracted position when the shear pin 78, which secures the collar 77 to the connector sleeve, is sheared, whereby the tool may be withdrawn from the well before the perforating operation of the punch has been commenced, or if commenced, before it is completed.

If desired, the stop member may be provided with a plurality of downwardly and outwardly inclined gripping teeth or serrations 82, as shown in Figure 14, instead of the coupling stop shoulder 75. The teeth 82 will engage and bite into the wall of a tubing section upon downward movement of the tool when the stop member is in extended position, so that the stop member need not engage in a coupling recess to limit further downward movement of the tool. Teeth on the tip of the dog 62 will also provide for actuation of the stop member to extended position without requiring that such dog tip engage in a coupling recess.

The foregoing description of the invention is explanatory only, and changes in the details of the construction illustrated may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

l. A well tool for perforating pipe including: a carrier; a punch mounted on the carrier for arcuate movement from an upper initial retracted position through an operative perforating position to a lower second retracted position; control means on said carrier engaging said punch for moving said punch on said carrier; means on said carrier biasing said control means longitudinally downwardly on said carrier, whereby said punch is biased from said initial retracted position toward said second retracted position; stop means movable on said lcarrier and initially releasably secured thereon in a position holding said punch in its initial retracted position, said stop means being releasable by downward force applied yto said carrier whereby said punch may move toward perforating position; said punch being adapted to perforate the pipe upon upward movement of the carrier after said punch is freed; and releasing means movably mounted on said cartier and initially releasably secured against movement thereon, said releasing means being releasable by further downward force applied to said carrier after the punch has been freed for perforating movement and before completion of said perforating movement, said releasing means when released being adapted to act upon the punch to move said punch back to its upper retracted position.

2. A well tool for perforating tubing comprising: an elongate tubular carrier movable through tubing and having a central longitudinal bore and a lateral window communicating with the bore; a punch mounted in said carrier for pivotal movement about an axis perpendicular to said longitudinal axis from a retracted position within said bore to an operative position wherein said punch extends outwardly of said carrier through said window into engagement with the tubing, said punch extending upwardly and outwardly from the carrier when in said operative position; a control means connected to said punch and movable downwardly and longitudinally in said borefor moving said punch from retracted to operative position; means biasing said control means downwardly in saidy bore; a connector sleeve slidably mounted on said carrier and having a first stop means engageable with a first stop shoulder of said carrier for limiting downward movement of said sleeve in said carrier and having a second stop means engageable with a second stop shoulder of said carrier for limiting upward movement of said sleeve in said carrier; a plunger having a lower end telescoped in the upper end of said connector sleeve and an upper end engaging said control means; relcasable means connecting said plunger and said sleeve holding said plunger in an upper position to prevent downward movement of said control means, said releasable means freeing said plunger for downward movement in said sleeve upon downward jars being imparted to said carrier; means on the upper end of said plunger limiting downward movement of said plunger in said sleeve, said second stop means being releasably secured to said sleeve, said second stop means being freed to move downwardly onv said sleeve upon downward jars being imparted to said carrier after said releasable means have been released whereby said carrier may move downwardly on said sleeve and said punch is moved back to retracted position; and expansible means mounted on said sleeve engageable with said irst stop shoulder to hold said carrier in lowered position on said sleeve whereby said tool may be raised through said tubing before a perforation is completed by said punch.

3. A well tool for perforating tubing comprising: a carrier movable through tubing by means of a ilexible line; a punch mounted for arcuate movement on said carrier and movable downwardly from an upper retracted position to an operative position in engagement with the tubing; control means on said carrier engaging said punch for moving said punch to said operative position; means biasing said control means downwardly on said carrier; stop means on said carrier for holding said punch in retracted position, said stop means being releasable by downward jars imparted to said carrier whereby said control means is freed to move said punch into operative position in engagement with said tubing, upward movement of said carrier after said punch is moved to operative position causing further downward arcuate movement of said punch past a position perpendicular to said tubing; and means mounted on said carrier and movable upwardly by downward force applied to said carrier to act upon and move said punch back to its original retracted position whereby said tool may be raised through the tubing before aperforation is made in the tubing by said tool.

4. A well tool for pertorating tubing comprising: a carrier movable through tubing by means of a exible line; positioning means mounted on said carrier for stopping downward movement of said tool in said tubing at a selected. location in said tubing; a punch pivotally mounted on said carrier for downward movement from an upper retracted position to an operative position in engagement with the tubing; control means on said carrier connected to said punch for moving said punch to said operative position; stop means on said carrier for holding said punch in retracted position, said stop means being releasable by downward jars imparted to said carrier when further downward movement of said tool in said tubing is prevented by said positioning means whereby said control meansA is freed to move said punch into operative position in engagement with said tubing, upward movement of said carrier after said punch is moved into operative position causing further downward pivotal movement of said punch past a position perpendicular to said tubing, said tubing being'penetrated by said punch during such upward movement of said carrier; and means mounted on said carrier and movable upwardly by downward jars applied to the carrier to act upon and move said control means to a position wherein the punch is moved back to its original retracted position whereby said tool may be raised through the tubing after the punch has, been moved to operative position and before perforation of the tubing is completed.

5. A well tool for perforating tubing comprising: an elongate tubular carrier movable through tubing andhaving a central longitudinal bore and a lateral window communicating with the bore; a punch mounted in said Car:- rier for pivotal movement about an axis perpendicular to said longitudinal axis from a retracted position within said bore to an operative position wherein saidpunch extends outwardly of said carrier through said window into engagement with the tubing, said punch extending upwardly and outwardly from the carrier when in said operative position; a control means connected to said punch and movable downwardly and longitudinally in said bore for moving said punch from extended to operative position; means biasing said control means downwardly in said bore; stop means secured to said carrier engaging said control means to prevent downward movement of said control means, said stop means being released by downward jars imparted to said carrier to allow said control means to move downwardly in said carrier whereby said punch is moved into operative position in engagement with said tubing and whereby upward movement of said carrier will cause said punch to penetrate said tubing; and means mounted on said carrier and movable upwardly by downward jars applied to the carrier to act upon and move said control means to a position wherein the punch is moved back to its original retractedv position whereby said tool may be raised through the tubing after the punch has been moved to operative position and before perforation of the tubing is completed.

6. A well 'tool for perforating tubing comprising: acarrier movable through tubing by means of a iiexible line; a punch pivotally mounted on said carrier fordownward movement from an upper retracted position to an operative position in engagement with the tubing; control means movable on said carrier connected to said punch for moving said punch to said operative position; stop means movable on said carrier and engageable with said control means for holding said punch in retracted position, said stop means being initially releasably secured in position holding said punch in retracted position and releasable by downward jars imparted to said carrier to permit said control means to move said punch into operative position in engagement with said tubing, said punch being swingable past perforating position to` a lower inoperative position upon upward movement of Ithe carrier after said punch has moved to operative position; releasing means movable on said carrier and initially secured against movement thereon, said releasing means being releasable after said stop means has been released to permit said punch to be moved to operative position and before the perforating operation has been concluded whereby said releasing means may act upon said control means to move the same to a position wherein the punch is moved back to its original retracted position, whereby the said tool may be raised through the tubing after the punch has been released for movement to operative position and before perforation of the tubing is completed.

7. A perforator for well tubing including: a body; positioning means carried by the body and engageable with a well tubing for limiting movement of the body in a downward direction therein; perforator means carried by the body and operable to perforate the well tubing on movement of the body in an upward direction in said well tubing; stop means movable on the body and initially releasably secured against movement on said body in a position holding said perforator means in an inoperative retracted position, said stop means being releasable by a downward force applied to the body after movement of the body has been stopped by the positioning means, whereby the perforator means may move to operative position; and releasing means movably mountedA on the body and initially releasably secured against movement thereon,l said releasing means beingreleasable by further downward force applied to the body after downward movement of the body has been stopped by said positioning means and after perforating movement of the perforator means has been commenced and before completion of said perforating movement, said releasing means when released being adapted to act upon the perforator means to move said perforator means back to its original inoperative position whereby said body may be moved upwardly in the well tubing without interference by said perforator means.

8. A well tool for perforating tubing comprising: an elongate tubular carrier movable through tubing and having a longitudinal bore and a lateral window communicating with the bore; a punch mounted in said carrier for pivotal movement about a transverse axis from a retracted position within said bore to an operative position wherein said punch extends outwardly of said carrier through said window and into engagement with the tubing, said punch extending upwardly and outwardly from the carrier when in said operative position; control means connected to said punch and movable longitudinally in the bore of said carrier for moving said punch between retracted and operative position; means biasing said control means downwardly in said bore; a stop plunger slidably mounted in said carrier; releasable means holding said plunger in an upper position wherein said plunger engages said control means and prevents downward movement thereof in the carrier; positioning means on the carrier movable into engagement with the well tubing for limiting downward movement of the tool in said well tubing; releasing means slidably mounted on said carrier; and second releasable means holding said releasing means in a lower inoperative position on said carrier, said second releasable means being released by downward force applied to the carrier after downward movement of the same has been stopped by said positioning means, whereby said releasing means may move upwardly in-said carrier to act upon said stop means and said control means to move said control means upwardly in the bore of the carrier to a position wherein the punch is moved back to original retracted position whereby the tool may be removed from the well tubing after the punch has been re.eased for movement to operative position and before the perforating operation has been completed,

9. A well tool for perforating tubing of the character set forth in claim 8 wherein: co-engageable means are provided on the carrier and the releasing means engageable upon upward movement of said releasing means for holding said releasing means in such upper position whereby the control means and the punch are positively held in original retracted position.

References Cited in the le of this patent UNITED STATES PATENTS 657,777 Kellogg Sept. 11, 1900 682,180 Eastwood et al. Sept. 10, 1901 1,642,970 Ritchey Sept. 20, 1927 1,774,911 Abercrombie Sept. 2, 1930 1,813,144 Carter et al. July 7, 1931 2,223,439 Bendeler et al. Dec. 3, 1940 2,328,782 Bynum Sept. 7, 1943 2,435,899 Page Feb. 10, 1948 

